C(OC(=O)[NH:7][CH:8]([C:12](=[O:23])[N:13]([CH3:22])[CH2:14][CH2:15][C:16]1[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=1)[CH:9]([CH3:11])[CH3:10])(C)(C)C.C(=O)(O)[O-].[Na+]>Cl.C(O)(C)C.C(OCC)(=O)C>[NH2:7][CH:8]([CH:9]([CH3:11])[CH3:10])[C:12]([N:13]([CH3:22])[CH2:14][CH2:15][C:16]1[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=1)=[O:23][2-Methyl-1-(methyl-phenethyl-carbamoyl)-propyl]-carbamic acid tert-butyl ester (3.79 g, 11.3 mmol) was added slowly in hydrochloric acid in isopropyl alcohol ([5M], 25 mL). The resulting mixture was stirred for 5 hours at room temperature, then the solvent was evaporated under reduced pressure to yield an oil. The oil was dissolved in ethyl acetate and treated with sodium bicarbonate solution. The organic layer was dried with MgSO4, filtered and the solvent evaporated under reduced pressure to yield an oil, which was purified by column chromatgraphy (10-50% EtOAc/heptane) to yield a residue.
Wird geladen…